In order to determine program effectiveness for incarcerated youth, it is necessary to understand the health and mental health needs of incarcerated youth. Using data from the Florida Department of Juvenile Justice (FDJJ) system’s Web-based monthly Health Services Report, this analysis examines the prevalence rates of physical and mental health diagnoses and service utilization for the 6-month period from November 2002 through April 2003. The study compared the prevalence rates of health conditions and service utilization for male residential programs (n =114), female residential programs (n = 31), and detention facilities (n = 25). Six different program types were examined for males: basic care and custody; boot camp; developmentally disabled; mental health; substance abuse; and sex offender. Results from the study indicate that residential programs tend to report higher rates of health service and treatment utilizations and higher rates of mental health disorders than detention centers, mental health disorders are more prevalent among youth in the juvenile justice system than are chronic physical health conditions, and females tend to have higher medical needs than males in a variety of areas. Tables